The present invention relates to a drive device for a vehicle, particularly a road or rail vehicle.
Generally speaking, the drive device for a vehicle is of the type comprising at least one drive motor and a transmission unit arranged after the motor and which is provided with an hydrodynamic clutch and/or an hydrodynamic torque converter. Such a drive device is known from German Offenlegungsschrift No. 2,618,073. Such patent discloses that an electric drive motor is connected via a hydrodynamic transmission, containing a torque converter and a clutch, to the drive wheels, the converter and the clutch being alternately switched into the power transmission system in dependence on the particular travelling speed.
Drive devices of the aforementioned type offer an alternative to the known electric-motor drives, the speed or torque of which is controlled by acting on the supply voltage or on the armature current with the aid of a high-power electronic switching device, for example, in direct current motors, a chopper, the switching conditions of which can be controlled, or, in the case of three-phase motors, a converter or current inverter which can be controlled in its output amplitude and frequency. The present alternative renders unnecessary such a high-power electronic system with its still considerable expenditure, and also its susceptibility to malfunction when used with the different types of current rectifiers. Thus the electro-hydraulic drive system continues to be viable and to have prospects for development.